I also like that money not currently taxed in underground economies, illegal aliens, etc. will get taxed with the Fair Tax.

Oh, how I love the young mind. At least I hope you're young and still relatively unjaded by life experience.

What exactly is it about the Fair Tax that you think is going to prompt the black marketeer (and his suppliers) to report their sales for the Fair Tax even though they don't report them for the income tax?

As for illegal aliens, you don't have the first clue. They certainly do pay taxes through withheld income and payroll taxes. They actually make a disproportionate contribution since they don't get the benefit of such programs as the Earned Income Tax Credit and Social Security benefits based on their work histories. I guess you assume that they all work off the books, which is a Fox News falsehood. If you live in an area with a sizeable immigrant population, volunteer to work with the Volunteer Income Tax Assistance (VITA) program. (Info available at www.irs.gov.) It's an eye-opener.